High Definition Multimedia Interface (HDMI) and Display Port (DP) can transmit ultra-high-definition signals such as 4K signals and 8K signals. Such ultra-high-definition signals have a property of high resolution without compression and lossless and a property of real-time, which can provide users with high-quality listening and visual experience.
The ultra-high-definition signal may be transmitted through a switchers or a distributor during a transmission process to meet demands of different users, and a chip of the switcher or the distributor includes multiple MOS switches connected in parallel and in series. This structure results in a linear increase in a parasitic capacitance and resistance of the switcher or the distributor, which leads to a rapid attenuation of the ultra-high-definition signal. The ultra-high-definition signal cannot be guaranteed to have the property of high resolution without compression and lossless and the property of real-time, which greatly reduces user experience.
At present, a chip of the switcher or the distributor is manufactured with an advanced chip manufacturing process, and a clock data recovery (CDR) circuit is designed in the chip of the switcher or the distributor at each level to remove an impact of bandwidth shortage and noises on signal quality. The function of switching or distributing the ultra-high-definition signal is achieved through multi-level cascading, and the chip of such switcher or distributor has a high cost and large power consumption. In order to save the cost, generally, the ultra-high-definition signal adopting the HDMI or DP protocol is unpacked and then compressed (such as JPEG H.264, etc.) and then converted into a network protocol. The signal is switched and distributed via a network switch or a Field Programmable Gate Array (FPGA) chip. The switched or distributed signal is decompressed and converted into the signal adopting the HDMI or DP protocol. However, with this method, the quality of the ultra-high-definition signal may be destroyed. Especially for moving pictures, the video may even be stopped. Furthermore, compression and decompression processes take a relatively long time, for application scenarios with high requirements of real-time, such as synchronous broadcast, seamless switching, games, this method cannot be used.
Therefore, how to achieve the function of switching or distributing the ultra-high-definition signal with a low-cost switcher or distributor on a premise of ensuring the quality of the ultra-high-definition signal has become a technical problem urgently to be solved by those skilled in the art.